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What is a food allergy?

What is a food allergy?

In the United Kingdom, food allergies impact 6-8% of young children and approximately 1-2% of adults, and have a considerable influence on the overall quality of life for affected families.

Here, Allergy London’s Paediatric allergist, Professor Adam Fox, shares crucial insights to unravel the complexities surrounding food allergies. This blog is focused on clarifying what a food allergy is and key aspects that contribute to a foundational understanding of food allergies.

What is a food allergy?

Which foods commonly trigger allergies in people?

Most individuals with food allergies react to a limited range of items. The primary allergen is often eggs, with other prevalent triggers including milk, nuts, sesame, fish, shellfish, wheat, soy, and kiwi. The specific foods causing allergies can vary based on the dietary patterns within a family and may differ across regions globally.

Delayed food allergies:

For delayed food allergies, particularly observed in younger children, distinctive challenges arise, making diagnosis challenging. Such symptoms, which are very common in children without food allergies, warrant consideration for allergy only if they are multiple, severe, persistent, and resistant to treatment.

These symptoms may include:

Unless the underlying allergy is identified and eliminated, symptoms may persist and intensify despite the aggressive use of treatments like steroids or other medications. However, delayed food allergy is rare and overdiagnosis can commonly occur.

Food allergies can emerge in adults as a newfound issue or may persist from childhood allergies. While certain childhood allergies, especially to milk, eggs, and wheat, may resolve over time, others, such as allergies to nuts, sesame, fish, and shellfish, may persist.

What are the indications and symptoms of a food allergy?

Typical symptoms associated with food allergies include the below mild reactions

Symptoms typically appear quickly after ingestion of the food causing the problem. Mild reactions also include swollen lips; the right thing to do if there of symptoms of this or itchy rash/hives is to give antihistamines and keep a close eye.

Recognising severe reactions

In more severe instances, food allergies can lead to:

The above are symptoms of a severe allergic reaction, Anaphylaxis, which is a medical emergency. If there is any suggestion that your child’s Airway, Breathing or Consciousness is involved then if you have been prescribed an Adrenaline autoinjector (AAI), use it immediately – this is a sign of Anaphylaxis, a severe allergic reaction; it’s important to use AAIs at the first sign of Anaphylaxis or if in doubt.

The approach to take in the event of Anaphylaxis (or if in doubt):

Professor Adam Fox along with Dr Nandinee Patel, Dr Ru-Xin Foong, Dr Paul Turner, and Professor Graham Roberts, collaborated to produce a recently developed leaflet. Created in partnership with allergy charities and patient groups, the leaflet is designed to empower and support families, caregivers, grandparents, and anyone tasked with the care of individuals with food allergies.

Read the new leaflet here.

This blog was written by Professor Adam Fox – November 2023. Professor Adam Fox can be found on Instagram @DrAdamFox – where you can follow his dedicated account for additional insights and advice on children’s allergies, designed to keep allergy families well-informed and aware.

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